For their work in atmospheric chemistry, particularly concerning the
formation and decomposition of ozone, the Royal Swedish Academy
of Sciences awarded the 1995 Nobel Prize in Chemistry to:

Professor Paul Crutzen of the Max Planck Institute for Chemistry in
Mainz, Germany. Dr. Crutzen was born in The Netherlands and is a
Dutch citizen.

Professor Mario Molina of the Department of Earth, Atmospheric, and
Planetary Sciences and Department of Chemistry at the
Massachusetts Institute of Technology in Cambridge, Massachusetts.
Dr. Molina was born in Mexico City and is now a U.S. citizen. He is a
member of the National Academy of Sciences.

Professor F. Sherwood Rowland of the Department of Chemistry at
the University of California, Irvine, California. Dr. Rowland was born
in Ohio. He is a member of the National Academy of Sciences, and is
currently its Foreign Secretary.

The announcement by the Royal Swedish Academy of Sciences stated
that these three scientists "...have all made pioneering contributions
in explaining how ozone is formed and decomposes through chemical
processes in the atmosphere. Most importantly, they have in this
way showed how sensitive the ozone layer is to the influence of
anthropogenic emissions of certain compounds. The thin ozone layer
has proved to be an Achilles heel that may be seriously injured by
apparently moderate changes in the composition of the atmosphere."

In 1970, Dr. Paul Crutzen "...showed that the nitrogen oxides NO and
NO2 react catalytically (without themselves being consumed)
with
ozone, thus accelerating the rate of reduction of the ozone
content....These nitrogen oxides are formed in the atmosphere
through the decay of the chemically stable nitrous oxide (N2O),
which
originates from microbiological transformations at the ground. The
connection demonstrated by Crutzen between microorganisms in the
soil and the thickness of the ozone layer is one of the motives for the
recent rapid development of research on global biogeochemical
cycles....This was also the start of intensive research into the
chemistry of the atmosphere which has made great progress during
the past several years."

"The next leap in our knowledge of ozone chemistry was in 1974,
when Mario Molina and Sherwood Rowland published their widely
noted Nature article on the threat to the ozone layer from CFC gases-
'freons'-used in spray bottles, as the cooling medium in refrigerators
and elsewhere, and plastic foams....Molina and Rowland realized that
the chemically inert CFC could gradually be transported up to the
ozone layer, there to be met by such intensive ultraviolet light that
they would be separated into their constituents, notably chlorine
atoms. They calculated that, if human use of CFC gases was to
continue at an unaltered rate, the ozone layer would be depleted by
many percent after some decades....Many were critical of Molina and
Rowland's calculations but yet more were seriously concerned by the
possibility of a depleted ozone layer. Today, we know that they were
right in all essentials. It was to turn out that they had even
underestimated the risk."

Thanks to the good scientific understanding of the ozone problem
achieved by Crutzen, Molina, and Rowland, as well as others who
have made crucial contributions, it has been possible to make far-
reaching decisions on regulating the release of gases that destroy
ozone. A protocol on the protection of the ozone layer was negotiated
under the auspices of the United Nations and signed in Montreal,
Canada, in 1987. "Since it takes some time for the ozone-destroying
gases to reach the ozone layer, we must expect the depletion, not
only over Antarctica but also over parts of the Northern Hemisphere,
to worsen for some years to come. Given compliance with the
[Montreal Protocol], the ozone layer should gradually begin to heal
after the turn of the century. Yet it will take at least 100 years
before it has fully recovered."